Compound centrifugal pump.



PATENTED JULY 30, 1907.

' E. w. RIGGS.

COMPOUND OBNTRIFUGAL PUMP.

APPLICATION FILED JULY 7, 1906 S SHEETS-SHEET l.

2% memes M ww PATENTED JULY :30, 190?: E. wgmees. COMPOUND GBNTRIFUGAL PUMP.

APPLIUATIONTILBD JULY 7,1905.

3 SHEETS-SHEET 2.

Smpawioz @214 WWW 5 2% 7k MW; W.

PATENTED JULY 30, 1907.

E. W. RIGGS.

' COMPOUND GBNTRIFUGAL PUMP.

APPLICATION FILED JULY7,1905.

3 SHEETS-SHEET 3.

6 f WJW ML/u Wihwmca view of my complete pump. Fig. 2 is a longitudinal,

UNITED STATES FATE T rich.

,E'RLANl) W.' RIGGS, OF BUTTE, MONTANA,-ASSIGNOR OF ONE-HALF TO MORRIS S. LARGEY,

-. OF BUTTE, MONTANA.

COMPOUND GENTRIFUGAL PIIMP.

Specification of Letters Patent.

Patented July 30, 1907.

Application filed-Tilly 7, 1995. Serial No. 268,598.

,tion is to provide a simple and economical device of this class, which with a small expenditure of power will lift a large amount of water to a considerable height.

With this objectin view, my invention consists in the construction and combinations of parts as hereinafter described and claimed.

In the accompanying drawings:-Figure l is a side vertical section of a part/thereof. Fig. 3 is a cross section of the pump casing. Fig. 4 is an end view of the same, and Figs. 5', 6 and 7 are diagrammatic views representing the arrangement and direction of rotation of the separate pumps, which togetherform the compound centriiugal pump. I

On a suitable foundation, (not shown) are located a series of standards arranged in pairs, or a, b b, and c 0, each pair serving as a bearing for one of the centrifugal pumps.

(1 represents the water inlet pipe which is provided with two branches 0 'and f, one of which leads into each end of the hollow-shaft g of the inner centrifugal pump h.- The shaft 9 is revolved by means of gear wheels 1' located in 'proximity -to the standards c. Suitable stuilingtboxes 'may oi course be used to prevent the water leaking at the pointwhere the pipes e and f come in proximity to the hollowshaft g. The ,inner pump h is provided with the usual curved blades j. Outside of the centrifugal pump it is a larger annular centrifugal pump It, provided with curved blades 1 arranged, however, in the opposite direction to the blades j on the pump it. The blades are carried by the side pieces or which are secured to the hollow shaft 12. which is mounted in the bearings b, gear wheels 0 being provided to drive the shaft 11.. Outside of'the pump is is arranged another annular centrifugal pump 10, provided with curved blades q oppositely arranged in relation to the blades Z, but approximately parallel to the blades j. The blades q are supported in side pieces 7 carried by the hollow. shaft s, which is supported in the standards a and revolved by means of the gear wheels t.

f two witnesses.

I have shown two gear wheels for 1 each hollow shaft, but obviously only one wheel for each shaft is necessary and any driving means can be substituted for the gear wheels shown. Stufling boxes are of course used where needed topreverit leakage.

The three centrifugal pumps are arranged concentrically as.sl1own within a casing u, volute shaped as shown in Fig. 3 and provided with a tapering discharge nozzle 10 which connects with the discharge pipe. As indicated in Figs. 5, 6 and 7, the pumps revolve in different directions, the inner one right handed for example, the intermediate one left handed, and the outer one right handed, and so on, as any desired number of concentric pumps can be used. Furthermore, the gearing is so arranged that the innermost pump travels the slowest, and that the speed of having the blades of the respective pumps curved in opposite directions, I consider of special importance. As the water or other liquid is thrown out, its pressure becomes greater, and each vane has a less distance proportionately to throw the water, and furthermore, the vanes are given a longer sweep, thus affording greater leverage.

While I have thus described my invention, I wish it to be distinctly understood that I do not limit myself to the exact details shown and described, as these might be varied in many respects without departing from the spirit of my invention. I

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States, is:. I I

1. In a compound centrifugal pump, the combination of a central centrifugal pump provided with curved vanes and mounted on a hollow shaft, :1 series of concentrically arranged annular centrifugal pumps mounted on hollow shafts and surrounding said iirstnamed pump, and means for driving said pumps at successively greater speeds from the central pump to the last one 0 1. the series, substantially as described. i H

'2. In a compound centrifugal pump, the combination of a-ccntral pump mounted on a hollow shaft'and provided with curved blades, a series of annular centrifugal pumps,

each mounted on a hollow'shaft and provided with curved vanes. the vanes on said pumps being curved in'opposite directions successively, means for driving said pumps at 'progrcssiwly greater speeds from the central pump outwvardly, a volute shaped casing surrounding said series of pumps, and inlet and discharge pipes, substantially as described.

In testimony whereof, I

afiix my signature, in presence ERLAND w. RIGGS.

Witnesses H. A. How, JOHN D. Hams- 

